Means and process for producing a false twist by friction



MEANS'AND PROCESS FOR l nopucnm A= FALSE TWIST 'BY FRICTION Filed Jaln. a. 1969 2 sheets sheet 1 INVENTOR Lows SABATQN ATTORNEYS Fil'ed Jan. 2, 19169 Sept. 3, 1910 g. SA -m 3,527,043

" MEANS AND PROCESS FOR PRODUCING A FALSE TWIST -BY FRICTION A. 2 Shee t S-Sheet z i 4 I 35 33- v 32 3\54 as 43 INVENTOR- Louis E Y SABATON United States Patent 49,500 Int. Cl. D0111 7/92; D02g 1/04 US. Cl. 5777.4 9 Claims ABSTRACT OF THE DISCLOSURE An apparatus and process for creating a false twist in a textile yarn by friction, said apparatus comprising at least one annular friction surface rotating about itself around a stationary axis, such annular friction surface being in contact at at least one point with a textile yarn in movement under tension, the yarn being guided to and from the annular friction ring by means located on the same side in relation to the entry and exit plane of the textile yarn, An intermediate guiding means may be provided to engage and guide the textile yarns in the annular space of the friction ring so as to maintain the textile yarn inside such base in contact with the friction ring.

Such an apparatus and process for creating a false twist therewith take advantage of a considerable peripheral diameter of the friction ring, a high rotational speed of such ring and a great ease in handling of the textile yarn.

The present invention is directed to novel apparatus and process for producing a false twist in a textile yarn through friction on a rotating element; more particularly, the present invention is directed to such an apparatus for creating a false twist on a textile yarn by friction wherein such apparatus takes into consideration at the same time the large peripheral diameter of a friction ring, a high rotational speed of such ring, and a great ease in handling of the textile yarn.

Many various processes and apparatus have been developed to produce bulked yarns, i.e., textured yarns, with a great 3-dimensional curling by twisting, fixing and subsequently untwisting. Generally, in conventionally employed processes this type of textured yarn is obtained in a continuous operation. Thus, for example, such a process makes use of false twist pins made up of turning tubes, provided with a twist locking device.

In addition to such conventionally employed processes and apparatus associated therewith various attempts have been made to develop a method of false twisting a textile yarn by friction. Such attempts to develop processes for false twisting by friction have generally involved a method by which the false twist is imparted to the textile yarn by an organ or device in movement, such as a belt, in tangential contact with the textile yarn, the yarn moving in a direction different from the direction of movement of surface of the organ or device. Genera ly, the movement of the textile yarn is substantially perpendicular to the direction of movement of such surface. While such methods of producing a false twist in a textile yarn by friction are extremely attractive from a purely conceptual view point, such methods have not been satisfactorily developed to date so that the conventional or traditional method of providing a false twist through a pin is resorted to in most instances.

The reasons for the insufiicient development of such processes for the development of a false twist in a textile yarn through friction are manifold. Primarily, however, such processes have not developed to a commercial standpoint since they require apparatus or devices and or special handling techniques which are relatively complex and do not have sufiicient output for commercial production.

In actuality it has been discovered that it is not a sim le matter to rotate a mobile surface at a great speed. In this connection, various proposals have been made in the past to employ turning rings that rotate the yarn by friction at the time the yarn passes through the friction rings. Here, however, two ditficulties are encountered. Firstly, the need to drive the contact surface at a very great speed brings one disadvantage to such a process and apparatus. Secondly, the need to pass the yarn through the turning rings brings into play a complication in the handling of the textile yarn, thereby bringing about a disadvantage to such systems.

For the above reasons it has been found easier to provide the false twisting by friction to have a rapid rotation of a turning organ or device with as small as dimensions as possible, particularly, the diameter.

In one embodiment, use has been made of annular friction surfaces with large peripheral dimensions, therefore offering a good ratio between the inside diameter of the turning organ and the diameter of the textile yarn. In this embodiment, the taut yarn is applied against the inside peripheral surface of the turning organ and necessarily goes right through, changing direction. This process gives somewhat good results and makes it possible to texture yarns of small count at speeds greater than those of the standard frames of false twist by pins about which the yarn is wrapped. However, since in this embodiment the yarn goes through the turning organ, complicated devices are necessary, such as those made up of a mobile ring or tube. Such a tube is mounted with a friction roller, driven in rotation, inside a stationary fitting, by its outside surface, which necessarily limits the speed of rotation of this tube. Moreover, when the yarn is handled (breaking, restarting), it is necessary to stop or disconnect the turning organ.

An example of such a system is shown, for example, in French Pat. No. 1,310,279 in the name of Kone Osokeyhtio. As discussed above, this French patent illustrates an apparatus for providing a false twist by means of friction, the apparatus having a turning organ or tube mounted to rotate on a frame so as to turn at a very high speed around its axis, the two ends each being provided with a ring having a high friction co-eificient. This patent, however, as described above, shows a system wherein the textile yarn passes through the rings, thereby creating the Inherent deficiencies and disadvantages prevously enumerated.

A further system illustrating such an apparatus for creating a false twist in a textile yarn is shown, for example, in French Pat. No. 1,158,478 in the name of British Nylon Spinners. This French patent describes a turning tube having its ends convexly shaped internally, and covered with a material having a high friction factor, the tube or yarn guide being characterized and arranged so that the angles of entry and exit of the yarn fall be tween 45 and Here again, as was the case with the previously described system this apparatus for creating a false twist in the textile yarn suffers from the same inherent deficiencies and disadvantages since the yarn is made to pass through the turning tube.

It can be seen from the above that it has been a long felt need of the art to provide a process and apparatus for producing a false twist in textile yarns by friction in a manner and with means which eliminate the inherent deficiencies and disadvantages of previously employed processes and apparatus. Thus, it has long been the desire of the art to provide such an apparatus and process which 3 combines both efficiency in the manner in which the false twist is produced coupled with ease of handling of the textile yarn. This has now been accomplished in accordance with the process and apparatus of the present invention.

Thus, it has been discovered in accordance with the present invention that the above disadvantages and deficiencies of previously employed processes and apparatus can be eliminated through the provision of an apparatus and process of using the same wherein such apparatus for producing a false twisting by friction comprises at least one annular friction surface in rotation on itself around a stationary axis, such annular friction surface being in contact at at least one point with a textile yarn in movement under tension, the apparatus being arranged so that the entry and exit sides of the textile yarn in the annular friction space are aligned. Such apparatus additionally comprises means for guiding the textile yarn under tension to and from the annular friction surface, such means being located on the same side of the annular surface as the entry and exit of the textile yarn.

Accordingly, it is a principal object of the present invention to provide a novel apparatus and method which eliminate the inherent deficiencies and disadvantages of those employed in accordance with the prior art.

A further object of the present invention is to provide a novel device for false twisting by friction which combines efiiciency in the production of the false twist and ease of handling of the textile yarn.

It is still a further object of the present invention to provide such a device or apparatus for creating a false twist in a textile yarn by friction, such apparatus comprising at least one annular friction surface in rotation on itself around a stationary axis, the friction surface being in contact at at least one point with a yarn in movement under tension, the entry and exit sides of the yarn in the annular friction space formed from the annular friction surface being aligned.

A still further object of the present invention is to provide such novel apparatus for creating a false twist in a textile yarn by friction wherein such apparatus contains guiding means to guide the yarn under tension to and from the annular friction surface, such means being located on the same side with respect to the entry and exit sections of the textile yarn.

Yet a further object of the present invention is to provide an intermediate guiding means for said novel apparatus for providing a false twist on textile yarns by friction, such intermediate guiding means comprising means comprising two arms, staggered in relation to one another at a certain angle, and pivoting on a fixed support.

Still further objects and advantages of the novel apparatus and process of the present invention will become more apparent from the following more detailed description thereof in conjunction with the drawings wherein:

FIG. 1 is a diagrammatic representation of the false twist apparatus in accordance with the present invention and an intermediate system for guiding the textile yarn in such apparatus;

FIG. 2 represents a schematic view of a false twist frame employing the false twist apparatus of the present invention;

FIG. 3 is a sectional view along line AA' of FIG. 2 showing the heating oven thereof;

FIG. 4 is a cross sectional view of the guiding element located ahead of the false twist apparatus.

The above objects and advantages of the novel process and apparatus of the present invention are achieved through the provision of a device or apparatus for creating a false twist by friction comprising at least one annular friction surface in rotation on itself around a stationary axis, in contact at at least one point with a yarn in movement under tension, the annular friction surface and false twist apparatus being so arranged that the entry and exit sides of the yarn in the annular friction space formed from the annular friction surface are aligned. Such a device provides a considerable peripheral diameter of a friction ring, a high rotational speed of such ring as well as a great ease in handling of the textile yarn. Such an apparatus as will be described in more detail hereinafter, additionally contains means for guiding the yarn under tension to and from the annular friction surface, such means being located on the same side with respect to both the entry and exit plane of the yarn. Thus, as was pointed out previously, in accordance with the novel process and apparatus of the present invention the yarn does not go through the false twist apparatus or tube and accordingly the apparatus and process of the present invention are provided with a great improvement with respect to the ease of handling of the textile yarn.

In the above general description of the novel apparatus and process of the present invention by annular space is meant the volume generated by the annular friction surface during its rotation. Accordingly, the expression entry side of the yarn in the annular space is meant that side of the textile yarn passing into the annular space for the first time. Similarly, the expression exit side is meant to embrace that face which the yarn leaving this annular space upon exiting the false twist apparatus. As can be seen from the above, the process and apparatus of the present invention are characterized particularly in that the yarn enters and leaves on the same side of the annular space.

Broadly, the apparatus or device of the present invention comprises, in. addition to the false twist device, means for guiding the yarn under tension to and from the annular friction surface or annular friction organ, such means being located on the same side with respect to the plane of entry and exit of the textile yarn and including means for intermediate guiding of the textile yarn making it possible to engage and guide the yarn in the annular space and to maintain it inside said space in contact with the friction organ. In practice, it is preferred in accordance with the process and apparatus of the present invention that the annular friction surface dis cussed above be circular in nature.

In the most general context, the false twist device employed in accordance with the present invention is composed of a turning tube, driven in rotation by a belt. The tube is provided with a hollow end portion covered inside with a ring and a material having a high friction factor, such material being one which is not abrasive, however. Such a material can comprise a conventional re-inforced elastomer such as employed, for example, in conjunction with the previously described French patents dealing with the production of false twist through friction. Such a material with a high friction factor but one which is not abrasive can comprise, for example, a rubber or polyurethane material, etc.

In a preferred embodiment, the means for intermediate guiding of the textile yarn is made up of a member comprising two arms, staggered in relation to one another at a certain angle, pivoting on a stationary support. Each arm carries a passage eye for the yarn. During operation, a first arm makes it possible to engage and guide the yarn in the annular space and to keep it inside said space in contact with the friction organ, the other arm making it possible to disengage the yarn from this annular space. In case of stopping, by pivoting of this intermediate guiding member, the first arm brings about the disengagement of the yarn from the annular space, the second arm serving only to guide the yarn.

According to another embodiment, this intermediate guiding means can also be made up of a simple or multiple arm moving inside the turning tube, particularly inside the annular space.

It is quite clear that the novel device or apparatus of the present invention is generally not employed alone in the formation of the false twisted textile yarn but is employed as a single element in an entire system utilized to achieve a finished textile yarn product. Thus, for exam ple, the novel false twisting device or apparatus of the present invention can be advantageously mounted on a frame in association with delivery means for the yarn, at least one means for fixing the curling associated with the textile yarn, means for guiding the yarn between such means for fixing the curling and the false twist assembly and finally, means for receiving the treated yarn. If, in fact, it is desired to obtain a fixed stretched yarn such frame mounting may additionally contain two means for fixing the curling arranged on both sides of the false twist device employed in accordance with the apparatus and process of the present invention.

In commercial practice, this frame can be made up of two frames placed facing each other. Advantageously, the yarns are guided from one frame to the other, in the upper part of the device at a height greater than that of the height of a man and/or below a platform located at the lower part of the frame but by making a suflicient space between this platform and the floor, for the installation of said yarn guiding elements.

, A means for fixing the curling, that is particularly indicated, is that made up of an open oven such as that described in French Pat. 1,395,038.

Likewise, the means for guiding between the heating oven and the false twist device can be made up of a channel whose cross section is in the form of a bow compass, i.e., in the form of a V whose point is replaced by an arc of more than 180.

The delivery means are made up, for example, of a creel from which the yarn is pulled by unwinding and by delivery rollers of any known type. The receiving means are also of any known type. Advantageously they are made up of devices giving directly usable windings, without special working, such as a long-path taking up device with driving by friction.

As indicated previously, the present invention is additionally directed to the process of producing a false twist by friction, such as, for example, produced in accordance with the utilization of the above broadly described apparatus. Such process comprises treating a thermoplastic textile yarn under tension and in movement by means of an annular friction surface in rotation on itself around a stationary axis and in contact with the textile yarn at at least one point. Such a process is characterized in that the textile yarn passes into and out of the annular space on the same side thereof such that the yarn goes through the annular space defined by the rotating friction surface 2n times, n being a whole number that can be equal to zero. As indicated in accordance to the apparatus of the present invention, the process of the present invention in accordance with the preferred embodiment is such that the directions of the yarn before and after the false twist device are substantially aligned.

Both the novel process and apparatus of the present invention will now be described by reference to a detailed description of the drawings. In such drawings, like numerals represent like elements throughout.

FIG. 1 illustrates the novel false twisting apparatus or device in accordance with the present invention. The device comprising a pin 1 made up of an annular portion 3 turning around an axis 5 which is driven by a belt 7. The pin carries inside a ring 9 of material with a high friction factor but not abrasive such as a conventional polyurethane elastomer. Means for handling the yarn and serving to guide the yarn in the pin and disengage it from the pin comprises a support carrying a double arm 13 mounted to rotate around a shaft 15. Each arm 16 and 17 is provided with an eye 18 and 19, respectively, for the passage of the yarn.

This double arm is blocked in working position by a stop 21 and in its disengagement position by another stop 23.

As shown in FIG. 1, the yarn passes into the annular space after passing over a return roller 51. This coupled with the means to guide the arm in the annular space allows the yarn to contact the annular friction surface of friction ring 9 in at least one location. Upon exiting pin 1 and the annular space provided by the rotation of the friction ring, the yarn passes on a second roller 52 which acts to pull the yarn away from the false twisting device. It can be seen from a review of FIG. 1 that the yarn enters and exits the annular space created by the rotation of the friction ring on the same side, that is, the yarn does not actually pass through the false twist device. This, .as indicated previously, provides an advantage associated with ease of yarn handling.

FIG. 2 illustrates an overall system employing the false twisting apparatus or device in accordance with the present invention. In accordance with FIG. 2 a creel 32 associated with a frame 31 carries bobbins of yarn, such as bobbin 33 from which yarn 4 is unwound. This, of course, is only a conventional feed system generally employed in the feeding of yarns for the false twisting and similar devices. It is, of course, obvious that it would not be beyond the scope of the present invention to replace such conventional feeding system with any other type of feeding system generally utilized.

Yarn 4 then passes into a tension device 35 which can be of any known type, such as a grill or cup tension device, then on a guide 36. It then goes through the space separating the two frames 31 and 37, at a sufiicient height not to block passage of the walk between the two frames.

Yarn 4 goes into a second frame 37 by a guide 38 and is pulled by a delivery system 49, then it goes into an oven 40.

Oven 40 is made up of a device such as that described in French Pat. 1,395,038. It presents particularly an open section such as that shown by FIG. 3. The yarn passes into a slot 41 and can be introduced or removed at any moment through orifice 42. The oven is provided with a, safety system (see FIG. 1) which, in case of interruption of the power, causes the pivoting of a cover 43 and an open return section 44 which removes the yarn from the heating plate 45.

At oven outlet 40, the yarn passes into an open return section 44 then goes into a shaped metal channel 47 whose section has the shape shown in FIG. 4. The length of this metal channel 47 is suflicient to permit a certain cooling of the yarn. It is advantageously between 50 cm. and 1.50 m. The yarn then goes into a false twist device 1 according to the present invention. Before going into the device for false twist by friction according to the present invention (FIG. 1), the yarn passes over a return roller 51.

After exiting the false twist device 1, the yarn then passes on a second roller 52 and is pulled from device 1 by a second delivery system 53 which regulates its speed in the device. Then it goes back across the passageway separating the two frames at a suflicient height not to block the passage of an operator and is received on frame 1 on the guiding system made up of one or more guides such as 54 and 55. The yarn is then wound on a device 56 such as a butterfly thread guide driven in a back and forth movement which distributes the yarn on support 57 driven tangentially by a spindle 58. The pressure of support 57 is constantly exerted with the increase of the height of the winding, thanks to an arm 59 pivoting around a stationary axis 60 and sliding at its free end on a stationary arm 61, thanks to an element 62, with a spring and eccentric clack, permitting arm 59 to move on stationary arm 61 only in a counterclockwise direction.

The advantage of such a winding system is to be able to obtain windings such as parallel windings whose dimensions and shape make them directly usable in further operations of transforming the yarn (weaving, knitting). Obviously, this device can be replaced by any other equivalent means.

It can be seen from the above description that the process and apparatus or device of the present invention provides numerous advantages over conventional devices employed for false twisting by friction. Thus, for example, the fact that the yarn does not have to travel axially through the turning tube makes it possible to achieve very high production speeds, the driving of the turning tube not having necessarily to take place on its outside peripheral portion. Thus, for example, high rotating speeds are easier to attain since the device or apparatus of the present invention does not require operational disengagement to effect a handling of the yarn and is mounted very simply and in a particularly efiicient manner. Thus, whereas it was necessary in accordance with prior art devices to completely stop the rotational movement of the twisting device in the case of the stopping, handling, or breaking of yarn. This is not required in accordance with the apparatus or process of the present invention. Thus, all that is required is to disengage the yarn by swinging or sliding of the intermediate guide means in a manner which does not involve any disengagement of the entire system.

Accordingly, the present invention is characterized by a considerable improvement in the speed of fabrication of textured yarns and by an appreciable reduction in installation costs.

The process of the present invention and the advantages attended therewith will now be illustrated by the following specific examples.

EXAMPLES 1 to 6 By means of the frame illustrated in FIG. 2 and a turning tube with an outside diameter of 60 mm. an inside diameter of 50 min, the length of the annular part 30 mm., provided inside with a friction ring of Vulkollan type polyurethane elastomer, with an outside diameter of 50 mm. and an inside diameter of 28 mom, a yarn of polyhexamethylene adipamide (polyamide 66) of 20 deniers/7 strands was textured under the various operating conditions given in Table I.

TABLE I Rate of Rate of pulling pulling of yarn Oven Speed of of yarn by 1st Temperrotation by 2nd Rate of deliverer ature of pin deliverer take up Ex. in m./min. in C. in r.p.m. in m./rnin. in m. min.

In all cases a very aesthetic textured yarn was produced by a very high winding speed. This, of course, is a great advantage from an industrial standpoint.

EXAMPLE 7 With the same device, a textured yarn is made of yarn of ethylene polyterephthalate 45 deniers, 22 strands under the following operating conditions:

Speed of the pin3,800 r.p.m.

Oven temperature230 C.

Speed of delivery of yarn218 m./ min.

Speed of drawing from 2nd deliverer-225 m./min. Winding speed210 m./min.

Here again, this example illustrates that in accordance with the present invention it is possible to produce textured yarns utilizing very high winding speeds. Moreover, in accordance with the examples, it was determined that the handling of the yarn could be conducted in a very simple and economic manner since disengagement of the pin is unnecessary in that the textile yarn does not pass actually through the same.

I claim:

1. Apparatus for creating a false twist in a textile yarn by friction comprising false twisting means comprising at least one annular friction surface rotating about a fixed axis and means for guiding a textile yarn to and from the annular space formed by the rotation of said anular friction surface, said means for guiding the textile yarn being located on the same side of said annular friction surface with respect to both the entrance and exit sections of the yarn guided through said apparatus, the yarn being in contact with said annular friction surface at least at one point thereof.

2. The apparatus of claim 1 wherein said guiding means includes intermediate guiding means effecting the engagement and guiding of the yarn in said annular space and in contact with said annular friction surface.

3. The apparatus of claim 2 wherein said intermediate guiding means comprises two arms, staggered in relation to one another and pivotable around a fixed axis, each arm having an eye for engagement of said textile yarn.

4. The apparatus of claim 2 wherein Said intermediate guiding means comprises a single or multiple arm moving inside a turning tube.

5. The apparatus of claim 1 wherein said false twisting means comprises a turning tube having a hollowed end portion.

6. The apparatus of claim 5 wherein the hollowed end portion of said turning tube is covered on its inner surface with a ring of material with a high friction coefficient.

7. In a system for creating a special effect on a textile yarn including a frame, means for delivering the yarn to said frame, means for fixing the curling of said yarn, false twist means, means for guiding the yarn between said means for fixing the curling and said false twist means, and means for receiving the finished yarn, the improvement which comprises a false twist means comprising at least one annular friction surface rotating about a fixed axis and means for guiding a textile yarn to and from the annular space formed by the rotation of said annular friction surface, said means for guiding the textile yarn being located on the same side of said annular friction surface as both the entrance and exit sections of the yarn guided through said apparatus, the yarn being in contact with said annular friction surface at least at one point thereof.

8. A process of texturing a textile yarn by the creation of a false twist by friction of a thermoplastic yarn under tension and in motion, which process comprises passing said textile yarn in contact at at least one point with an annular friction surface of a false twist means in rotation on itself around a stationary axis, said process being characterized on that said yarn passes 211 times through an annular space defined by said friction surface in rotation, 11 being an integer of 0 or more.

9. The process of claim 8 wherein the directions of said yarn both ahead of and after said false twist means are substantially aligned.

References Cited UNITED STATES PATENTS 2,718,111 9/1955 Brown 5777.4 2,936,567 5/1960 Russell et al. 5777.4 3,029,591 4/1962 Scragg et al. 5777.4 XR 3,066,473 12/1962 Maeda 57--77.4 3,114,231 12/1963 Selling et a1. 5777.4 XR 3,166,881 l/1965 Servage 5734 FOREIGN PATENTS 850,079 9/1960 Great Britain.

OTHER REFERENCES German Printed Publication, June 1967, Glantstoif, 5777.4.

DONALD E. WATKINS, Primary Examiner US. Cl. X.R. 57-51.6, 157 

